Infectious disease has now entered a post-antibiotic era where multi-drug resistance is increasingly common. There is an immediate need for new diagnostics that can determine the susceptibility of pathogenic bacteria to antibiotics rapidly and accelerate the administration of targeted therapy for optimal patient outcomes. BioSense Technologies proposes the development of a new phenotypic assay for determining antibiotic minimum inhibitory concentrations (MIC) in 60 minutes. The technology monitors the development of antibiotic- induced cellular stress as an early response for determining the effect of therapeutic agents on cellular suspensions. The immediacy and ubiquity of the response enables near real-time assessment of all bacterial species treated with drugs having different mechanisms of action. We propose to demonstrate feasibility of the approach by measuring the early responses of isolates spanning a wide range of MIC values for six organism-antibiotic combinations to construct susceptibility response profiles and corresponding database. The Phase I effort will conclude with a blinded study to validate the technical approach. In Phase II additional organism-antibiotic combinations will be studied including all important resistance mechanisms and platform hardware will be expanded to accommodate measurement of a larger number of therapeutic agents.